eChapters

Introduction

A solar collector, the special energy exchanger, converts solar irradiation energy either to the thermal energy of the working fluid in solar thermal applications, or to the electric energy directly in Photovoltaic (PV) applications. For solar thermal applications, solar irradiation is absorbed by a solar collector as heat which is then transferred to its working fluid (air, water or oil). The heat carried by the working fluid can be used to either provide domestic hot water/heating, or to charge a thermal energy storage tank from which the heat can be drawn for use later (at night or cloudy days). Solar collectors are usually classified into two categories according to concentration ratios: non-concentrating collectors and concentrating collectors. A non-concentrating collector has the same intercepting area as its absorbing area, whilst a sun-tracking concentrating solar collector usually has concave reflecting surfaces to intercept and focus the solar irradiation to a much smaller receiving area, resulting in an increased heat flux so that the thermodynamic cycle can achieve higher Carnot efficiency when working under higher temperatures.

Introduction

Water is the primary source of life for mankind and one of the most basic necessities for crop production. The demand for water to irrigate the crops is increasing. For sustainable production from agricultural farms, irrigating the crops at right stages is highly important. Even in rainfed situation, lifesaving irrigation during long dry spell has also been found beneficial for crop survival and to obtain the targeted yield. Considering the depletion of groundwater below the critical zone in most part of the country, energy intensive pumping for irrigation is not a viable option. Therefore utilization of available runoff water through surface storage systems followed by pumping may be a potential solution to achieve the set goal of ‘crop per drop’ mission. In this connection, micro-irrigation system including drippers and sprinklers is of great importance. However, ensured power supply is essential to operate the micro-irrigation system even in remote areas. Reliable solar photovoltaic (PV) pumps are now emerging in the market and are rapidly becoming more attractive than the traditional power sources. These technologies, powered by renewable energy sources, are especially useful in remote locations where a steady fuel supply or electricity supply is problematic. About 16 million electric pumps and 7 million diesel pumps are in operations in the country for irrigation purpose; however they are highly energy intensive. Moreover, diesel operated and electrified pumps directly or indirectly emit large amount of CO₂ gas in atmosphere and hence are not environment friendly. To meet the energy demand for irrigation, solar PV pumps have been introduced under the off-grid power generation category of National Solar Mission (NSM) with a target of 1000 MW by the end of phase II (2013-2017). The target has been revised in 2015 to a total grid connected solar power generation of 1,00,000 MW comprising 40,000 MW roof top generation and 60,000 MW grid connected solar power plants (Resolution of MNRE, Govt of India, No. 30/80/2014-15/ NSM dated 1^st July 2015).

PV clad structures and hybrid devices for rural and agricultural applications have been developed after considering different design aspects, climatic parameters, solar radiation availability on different planes, heat transfer coefficients, performance of PV in arid region and inter phasing of different components while keeping in view, practicality, application and ease of operation. Performance of the developed systems was studied, mathematical model developed and energy savings worked out for techno-economic considerations. The chronology and details of the developed PV structures and hybrid devices are as follows:

Green structure for environmental control

First of all a Quonset type environment control structure having a length of 5.3 m and width 4 m was fabricated with angle iron and iron rods and it was covered by agro-net (75%) having surface area of about 55 m². The structure having a volume of 33 m³ was fixed with long side along east west direction and had provisions for incorporation of misting unit on west side and a door on east.

The chapter will delve into the fundamental physics governing energy exchange at the Earth’s surface and how water is managed within the soil profile. These concepts are crucial for understanding microclimate, evapotranspiration, and overall water availability for crops. This chapter explores the intricate interactions between incoming solar radiation, its transformation into various energy forms at the Earth’s surface, and the dynamic movement and storage of water within the soil. Understanding these processes is vital for agricultural meteorology, as they directly influence temperature, humidity, and water availability for plant growth.The Earth’s surface, particularly a vegetated land surface, continuously exchanges energy with the atmosphere. The Surface Energy Budget quantifies these energy fluxes, explaining how incoming solar radiation is partitioned. It operates on the principle of conservation of energy: the energy received must equal the energy expended or stored (Fig. 6.1). The Earth’s surface energy budget numbers derived from Kiehl-Trenberth 1997. The surface of the Earth is cooled 40 W/m2 by radiation; this part of surface radiation is radiated straight into Space. 324 W/m2 of all outgoing surface radiation returns nearly simultaneously as back radiation. The remaining 26 W/m2 of surface radiation is absorbed by greenhouse gases and results in the warming of the atmosphere near the

ABSTRACT

Ground water is an important source of water supply throughout the world for irrigation, industries, municipalities and rural homes and the dependence of an Indian village is on its water source only. The quality of water is as important as its quality. The quality required of a groundwater supply depends on its purpose such as drinking or agricultural or industries. To establish quality criteria, measures of chemical, physical, biological constituents must be specified as well as standard methods for reporting and comparing results of water analysis .For that a case study is to be made. Cuddalore district is a rapidly growing urbanized industrial area and lies at the east coast of Tamil Nadu in India. It mainly depends on the ground water. Water quality data for the observation wells from the year 1989 to 1999 were collected and spatial distribution of the groundwater quality is analysed using geographic information system. The important factors such as pH, Chloride shows higher level and generally occur in the central belt of the study area which is rich in mineral wealth. Compared to the eastern half the western half shows better quality of water. From the analysis, 80% of the study area is suitable for agricultural purpose and 75% of the study area is suitable for domestic and drinking purpose.

Introduction

For optimum use of harvested rain water in surface reservoir like farm ponds or tankas, small sized solar PV pumping systems with 1 hp AC and DC motor were experimentally tested at research farms of ICAR-Central Arid Zone Research Institute, Jodhpur (Fig. 16.1). Total suction head in both pumps was about 5 m. Among two installed pumps, the system with AC pump consisted of 1400 Wp (200 Wp × 7) whereas the DC pump consisted of PV array of 920 Wp (230Wp × 4). Each PV panel of AC solar pump was connected in series, which was further connected with an inverter to generate AC output of about 220-240 volt and 4-4.2 ampere. In case of DC solar pump, panels are connected in parallel to generate DC output of 40-50 volt and 15-20 ampere.

Introduction

Cultivation of crops in greenhouse or protected structure has been increased tremendously in recent times and also has been spread from temperate regions to the warmer regions of tropics and subtropics. Plentiful technologies have been developed for heating the inside environment of greenhouse for optimum plant growth (Sethi et al. 2013). However, in hot arid areas, cultivation in greenhouse is very difficult as the temperature reaches to a very high level to sustain plant growth (Pek and Hayles 2004, Saran et al. 2010). Under such situation requirement for cooling the greenhouse microclimate environment is the necessity, but is very energy and water intensive. Hence, in such regions, reduction of air temperature inside the greenhouse or the regulation of temperature closer to the ambient temperature during summer is necessary for successful crop production. A typical diurnal variation of temperature and global solar radiation during late winter months inside a shade net structure has been plotted in Fig. 18.1. It has been found that global solar radiation has been decreased to almost 1/3 of the radiation received outside by using 75% shade net cover. The temperature inside structure during morning time has also been found higher than outside temperature and in summer such increase is expected to be much higher.

Therefore, cooling is considered as the basic necessity for greenhouse crop production in tropical and subtropical regions to overcome the problems of high temperatures during summer months. Development of suitable cooling system that provides congenial microclimate for crop growth is a difficult task as the design is closely related to the local environmental conditions. Different cooling techniques for greenhouse crop cultivation may be found in Kumar et al. (2009). Fan pad cooling system has been widely used for greenhouse cultivation however, requires large amount of water during evaporation based cooling. Since water resources are becoming scarce in future such fan-pad cooling system may not be viable in future specifically in hot arid region.

ABSTRACT

The occurrence of fluoride more than permissible limit has been observed in ground water near Danishpet, Rajammannar Colony, Vayapurikombai, Melkombai, Umbilikampatty, Andikottai HC in Kadyampatty area, Salem district. Fluoride reaches to a maximum of 2.8 mg/l. Fluoride concentrations in ground water in various areas are as follows: Danishpet(2.0mg/l), Rajammannar Colony (2.8mg/l), Vayapurikombai (2.4 mg/l), Melkombai (2.4mg/l), Umbilikampatty (2.2 mg/l), and Andikottai HC (2 mg/l).. Granite gneiss and associated secondary vein filling minerals may be the source of high fluoride in ground water. The high concentration of Fluoride in ground water has led to human health hazard in the form of dental and skeletal deformation in the parts of Danishpet, Rajammar Colony, Vayapurikombai, Melkombai, Umbilikampatti and Andikottai HC villages.

The United Nations had declared the decade of 90s (1990-1999) as the International Decade for National Disaster Risk Reduction to enable developing countries to build up their capacity to cope up with disasters. The Government of India also set up a High Powered Committee (HPC), in August 1999, to review the preparedness and mitigation of natural and manmade disasters and recommend measures for strengthening the organisational structures and a comprehensive model plan for management of disasters at national, state and district level. The HPC after due deliberatons submitted the report in Feb. 2001. The HPC identified the disasters under the following types (categories) :

Throughout history, humanity has been locked in a perpetual struggle with the forces of nature, and one of the most insidious and destructive of these forces is drought. A creeping disaster that seeps into the very fabric of communities, drought leaves behind a trail of devastation and despair, testing the resilience of societies and pushing the boundaries of human endurance. From the ancient civilizations of Mesopotamia to modern-day cities, droughts have ravaged the landscape, claiming lives, destroying livelihoods, and reshaping the course of human history. • The impact of drought is far-reaching and multifaceted, affecting not just the environment, but also the economy, health, and overall wellbeing of individuals and communities. Crops wither and die, livestock perish, and entire ecosystems are disrupted, leading to food and water shortages that can have catastrophic consequences. The economic toll of drought can be equally devastating, as agriculture, industry, and tourism is severely impacted, leading to widespread unemployment and poverty. • What makes droughts particularly pernicious is their ability to unfold slowly, their effects accumulating over time,

1.1 Introduction

The life on the earth is driven by the energy available in the various forms. Energy is the most crucial entity in development of the world. The sufficient and sustainable supply of energy is deciding factor in the global energy market. Solar energy from the sun is the basic source of energy on the earth which further manifest into the other energy forms. However, the fossil fuel energy is widely used energy on the larger scale on commercial basis due to its availability and technological advancement in handling these fossil fuels.

Introduction

Landslides are simply defined as mass movement of rock, debris or earth down a slope and have come to include broad range of motions whereby falling, sliding and flowing under the influence of gravity dislodges earth material. They often take place in conjunction with earthquakes, floods and volcanoes. At times, prolonged rainfall cause heavy landslides, that block the flow of river for quite sometime.

INTRODUCTION

Remote Sensing is an indigenous tool for the Environmental Impact Assessment study. It plays vital role in preparing various thematic maps for understanding the changes that have taken place in an area before and after the establishment activities. In this study we have utilized the capability of the remote sensing techniques in understanding the mining environment. Our study area is in and around the Dalmiapuram Cement Industry in the central part of Tamil Nadu state and it covers part of Trichy and Perambalur districts. It falls between 11₀ 02’ 42’’and 1₀ 03’ 08’’E and 79₀ 09’ 39’’and 79₀ 10’ 30’’N.Dalmiapuram Cement Industry is located in the Kovandakurichi village of Pullambadi block, Trichy district. The mines for cement manufacturing are Perianagalur (PNR), Periathirukonam (PTK), Kallakudi (KLK), Kovandakurichi (KVK) and A&K Mines.

The litho units are Limestone beds containing various proportions of bioclastic and siliciclastic materials. They show wackstone to rudstone fabric and have clasts of re-deposited bound stones. Deposition in a periodically restricted shallow marine setting was indicated by lithological and faunal information. Lower contact is an unconformity surface associated with marine flooding and the upper contact is non-depositional and erosional with overlying biostormal member.